Linux Audio

Check our new training course

Loading...
v4.6
 
  1/*
  2 * Imagination Technologies Pulse Width Modulator driver
  3 *
  4 * Copyright (c) 2014-2015, Imagination Technologies
  5 *
  6 * Based on drivers/pwm/pwm-tegra.c, Copyright (c) 2010, NVIDIA Corporation
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License as published by
 10 * the Free Software Foundation; either version 2 of the License.
 11 */
 12
 13#include <linux/clk.h>
 14#include <linux/err.h>
 15#include <linux/io.h>
 16#include <linux/mfd/syscon.h>
 17#include <linux/module.h>
 18#include <linux/of.h>
 19#include <linux/of_device.h>
 20#include <linux/platform_device.h>
 
 
 21#include <linux/pwm.h>
 22#include <linux/regmap.h>
 23#include <linux/slab.h>
 24
 25/* PWM registers */
 26#define PWM_CTRL_CFG				0x0000
 27#define PWM_CTRL_CFG_NO_SUB_DIV			0
 28#define PWM_CTRL_CFG_SUB_DIV0			1
 29#define PWM_CTRL_CFG_SUB_DIV1			2
 30#define PWM_CTRL_CFG_SUB_DIV0_DIV1		3
 31#define PWM_CTRL_CFG_DIV_SHIFT(ch)		((ch) * 2 + 4)
 32#define PWM_CTRL_CFG_DIV_MASK			0x3
 33
 34#define PWM_CH_CFG(ch)				(0x4 + (ch) * 4)
 35#define PWM_CH_CFG_TMBASE_SHIFT			0
 36#define PWM_CH_CFG_DUTY_SHIFT			16
 37
 38#define PERIP_PWM_PDM_CONTROL			0x0140
 39#define PERIP_PWM_PDM_CONTROL_CH_MASK		0x1
 40#define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch)	((ch) * 4)
 41
 
 
 42/*
 43 * PWM period is specified with a timebase register,
 44 * in number of step periods. The PWM duty cycle is also
 45 * specified in step periods, in the [0, $timebase] range.
 46 * In other words, the timebase imposes the duty cycle
 47 * resolution. Therefore, let's constraint the timebase to
 48 * a minimum value to allow a sane range of duty cycle values.
 49 * Imposing a minimum timebase, will impose a maximum PWM frequency.
 50 *
 51 * The value chosen is completely arbitrary.
 52 */
 53#define MIN_TMBASE_STEPS			16
 54
 
 
 55struct img_pwm_soc_data {
 56	u32 max_timebase;
 57};
 58
 59struct img_pwm_chip {
 60	struct device	*dev;
 61	struct pwm_chip	chip;
 62	struct clk	*pwm_clk;
 63	struct clk	*sys_clk;
 64	void __iomem	*base;
 65	struct regmap	*periph_regs;
 66	int		max_period_ns;
 67	int		min_period_ns;
 68	const struct img_pwm_soc_data   *data;
 
 
 69};
 70
 71static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip)
 72{
 73	return container_of(chip, struct img_pwm_chip, chip);
 74}
 75
 76static inline void img_pwm_writel(struct img_pwm_chip *chip,
 77				  u32 reg, u32 val)
 78{
 79	writel(val, chip->base + reg);
 80}
 81
 82static inline u32 img_pwm_readl(struct img_pwm_chip *chip,
 83					 u32 reg)
 84{
 85	return readl(chip->base + reg);
 86}
 87
 88static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 89			  int duty_ns, int period_ns)
 90{
 91	u32 val, div, duty, timebase;
 92	unsigned long mul, output_clk_hz, input_clk_hz;
 93	struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
 94	unsigned int max_timebase = pwm_chip->data->max_timebase;
 
 95
 96	if (period_ns < pwm_chip->min_period_ns ||
 97	    period_ns > pwm_chip->max_period_ns) {
 98		dev_err(chip->dev, "configured period not in range\n");
 99		return -ERANGE;
100	}
101
102	input_clk_hz = clk_get_rate(pwm_chip->pwm_clk);
103	output_clk_hz = DIV_ROUND_UP(NSEC_PER_SEC, period_ns);
104
105	mul = DIV_ROUND_UP(input_clk_hz, output_clk_hz);
106	if (mul <= max_timebase) {
107		div = PWM_CTRL_CFG_NO_SUB_DIV;
108		timebase = DIV_ROUND_UP(mul, 1);
109	} else if (mul <= max_timebase * 8) {
110		div = PWM_CTRL_CFG_SUB_DIV0;
111		timebase = DIV_ROUND_UP(mul, 8);
112	} else if (mul <= max_timebase * 64) {
113		div = PWM_CTRL_CFG_SUB_DIV1;
114		timebase = DIV_ROUND_UP(mul, 64);
115	} else if (mul <= max_timebase * 512) {
116		div = PWM_CTRL_CFG_SUB_DIV0_DIV1;
117		timebase = DIV_ROUND_UP(mul, 512);
118	} else if (mul > max_timebase * 512) {
119		dev_err(chip->dev,
120			"failed to configure timebase steps/divider value\n");
121		return -EINVAL;
122	}
123
124	duty = DIV_ROUND_UP(timebase * duty_ns, period_ns);
125
126	val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
 
 
 
 
127	val &= ~(PWM_CTRL_CFG_DIV_MASK << PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm));
128	val |= (div & PWM_CTRL_CFG_DIV_MASK) <<
129		PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm);
130	img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
131
132	val = (duty << PWM_CH_CFG_DUTY_SHIFT) |
133	      (timebase << PWM_CH_CFG_TMBASE_SHIFT);
134	img_pwm_writel(pwm_chip, PWM_CH_CFG(pwm->hwpwm), val);
 
 
 
135
136	return 0;
137}
138
139static int img_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
140{
141	u32 val;
142	struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
 
143
144	val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
 
 
 
 
145	val |= BIT(pwm->hwpwm);
146	img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
147
148	regmap_update_bits(pwm_chip->periph_regs, PERIP_PWM_PDM_CONTROL,
149			   PERIP_PWM_PDM_CONTROL_CH_MASK <<
150			   PERIP_PWM_PDM_CONTROL_CH_SHIFT(pwm->hwpwm), 0);
151
152	return 0;
153}
154
155static void img_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
156{
157	u32 val;
158	struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
159
160	val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
161	val &= ~BIT(pwm->hwpwm);
162	img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
163}
164
165static const struct pwm_ops img_pwm_ops = {
166	.config = img_pwm_config,
167	.enable = img_pwm_enable,
168	.disable = img_pwm_disable,
169	.owner = THIS_MODULE,
170};
171
172static const struct img_pwm_soc_data pistachio_pwm = {
173	.max_timebase = 255,
174};
175
176static const struct of_device_id img_pwm_of_match[] = {
177	{
178		.compatible = "img,pistachio-pwm",
179		.data = &pistachio_pwm,
180	},
181	{ }
182};
183MODULE_DEVICE_TABLE(of, img_pwm_of_match);
184
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
185static int img_pwm_probe(struct platform_device *pdev)
186{
187	int ret;
188	u64 val;
189	unsigned long clk_rate;
190	struct resource *res;
191	struct img_pwm_chip *pwm;
192	const struct of_device_id *of_dev_id;
193
194	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
195	if (!pwm)
196		return -ENOMEM;
197
198	pwm->dev = &pdev->dev;
199
200	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
201	pwm->base = devm_ioremap_resource(&pdev->dev, res);
202	if (IS_ERR(pwm->base))
203		return PTR_ERR(pwm->base);
204
205	of_dev_id = of_match_device(img_pwm_of_match, &pdev->dev);
206	if (!of_dev_id)
207		return -ENODEV;
208	pwm->data = of_dev_id->data;
209
210	pwm->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
211							   "img,cr-periph");
212	if (IS_ERR(pwm->periph_regs))
213		return PTR_ERR(pwm->periph_regs);
214
215	pwm->sys_clk = devm_clk_get(&pdev->dev, "sys");
216	if (IS_ERR(pwm->sys_clk)) {
217		dev_err(&pdev->dev, "failed to get system clock\n");
218		return PTR_ERR(pwm->sys_clk);
219	}
220
221	pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm");
222	if (IS_ERR(pwm->pwm_clk)) {
223		dev_err(&pdev->dev, "failed to get pwm clock\n");
224		return PTR_ERR(pwm->pwm_clk);
225	}
226
227	ret = clk_prepare_enable(pwm->sys_clk);
228	if (ret < 0) {
229		dev_err(&pdev->dev, "could not prepare or enable sys clock\n");
230		return ret;
231	}
232
233	ret = clk_prepare_enable(pwm->pwm_clk);
234	if (ret < 0) {
235		dev_err(&pdev->dev, "could not prepare or enable pwm clock\n");
236		goto disable_sysclk;
 
 
 
237	}
238
239	clk_rate = clk_get_rate(pwm->pwm_clk);
240	if (!clk_rate) {
241		dev_err(&pdev->dev, "pwm clock has no frequency\n");
242		ret = -EINVAL;
243		goto disable_pwmclk;
244	}
245
246	/* The maximum input clock divider is 512 */
247	val = (u64)NSEC_PER_SEC * 512 * pwm->data->max_timebase;
248	do_div(val, clk_rate);
249	pwm->max_period_ns = val;
250
251	val = (u64)NSEC_PER_SEC * MIN_TMBASE_STEPS;
252	do_div(val, clk_rate);
253	pwm->min_period_ns = val;
254
255	pwm->chip.dev = &pdev->dev;
256	pwm->chip.ops = &img_pwm_ops;
257	pwm->chip.base = -1;
258	pwm->chip.npwm = 4;
259
260	ret = pwmchip_add(&pwm->chip);
261	if (ret < 0) {
262		dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret);
263		goto disable_pwmclk;
264	}
265
266	platform_set_drvdata(pdev, pwm);
267	return 0;
268
269disable_pwmclk:
270	clk_disable_unprepare(pwm->pwm_clk);
271disable_sysclk:
272	clk_disable_unprepare(pwm->sys_clk);
 
 
273	return ret;
274}
275
276static int img_pwm_remove(struct platform_device *pdev)
277{
278	struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev);
279	u32 val;
280	unsigned int i;
 
 
 
 
 
281
282	for (i = 0; i < pwm_chip->chip.npwm; i++) {
283		val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
284		val &= ~BIT(i);
285		img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
 
 
 
 
 
 
 
286	}
287
288	clk_disable_unprepare(pwm_chip->pwm_clk);
289	clk_disable_unprepare(pwm_chip->sys_clk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
290
291	return pwmchip_remove(&pwm_chip->chip);
 
 
 
292}
 
 
 
 
 
 
 
 
293
294static struct platform_driver img_pwm_driver = {
295	.driver = {
296		.name = "img-pwm",
 
297		.of_match_table = img_pwm_of_match,
298	},
299	.probe = img_pwm_probe,
300	.remove = img_pwm_remove,
301};
302module_platform_driver(img_pwm_driver);
303
304MODULE_AUTHOR("Sai Masarapu <Sai.Masarapu@imgtec.com>");
305MODULE_DESCRIPTION("Imagination Technologies PWM DAC driver");
306MODULE_LICENSE("GPL v2");
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Imagination Technologies Pulse Width Modulator driver
  4 *
  5 * Copyright (c) 2014-2015, Imagination Technologies
  6 *
  7 * Based on drivers/pwm/pwm-tegra.c, Copyright (c) 2010, NVIDIA Corporation
 
 
 
 
  8 */
  9
 10#include <linux/clk.h>
 11#include <linux/err.h>
 12#include <linux/io.h>
 13#include <linux/mfd/syscon.h>
 14#include <linux/module.h>
 15#include <linux/of.h>
 
 16#include <linux/platform_device.h>
 17#include <linux/pm_runtime.h>
 18#include <linux/property.h>
 19#include <linux/pwm.h>
 20#include <linux/regmap.h>
 21#include <linux/slab.h>
 22
 23/* PWM registers */
 24#define PWM_CTRL_CFG				0x0000
 25#define PWM_CTRL_CFG_NO_SUB_DIV			0
 26#define PWM_CTRL_CFG_SUB_DIV0			1
 27#define PWM_CTRL_CFG_SUB_DIV1			2
 28#define PWM_CTRL_CFG_SUB_DIV0_DIV1		3
 29#define PWM_CTRL_CFG_DIV_SHIFT(ch)		((ch) * 2 + 4)
 30#define PWM_CTRL_CFG_DIV_MASK			0x3
 31
 32#define PWM_CH_CFG(ch)				(0x4 + (ch) * 4)
 33#define PWM_CH_CFG_TMBASE_SHIFT			0
 34#define PWM_CH_CFG_DUTY_SHIFT			16
 35
 36#define PERIP_PWM_PDM_CONTROL			0x0140
 37#define PERIP_PWM_PDM_CONTROL_CH_MASK		0x1
 38#define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch)	((ch) * 4)
 39
 40#define IMG_PWM_PM_TIMEOUT			1000 /* ms */
 41
 42/*
 43 * PWM period is specified with a timebase register,
 44 * in number of step periods. The PWM duty cycle is also
 45 * specified in step periods, in the [0, $timebase] range.
 46 * In other words, the timebase imposes the duty cycle
 47 * resolution. Therefore, let's constraint the timebase to
 48 * a minimum value to allow a sane range of duty cycle values.
 49 * Imposing a minimum timebase, will impose a maximum PWM frequency.
 50 *
 51 * The value chosen is completely arbitrary.
 52 */
 53#define MIN_TMBASE_STEPS			16
 54
 55#define IMG_PWM_NPWM				4
 56
 57struct img_pwm_soc_data {
 58	u32 max_timebase;
 59};
 60
 61struct img_pwm_chip {
 
 
 62	struct clk	*pwm_clk;
 63	struct clk	*sys_clk;
 64	void __iomem	*base;
 65	struct regmap	*periph_regs;
 66	int		max_period_ns;
 67	int		min_period_ns;
 68	const struct img_pwm_soc_data   *data;
 69	u32		suspend_ctrl_cfg;
 70	u32		suspend_ch_cfg[IMG_PWM_NPWM];
 71};
 72
 73static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip)
 74{
 75	return pwmchip_get_drvdata(chip);
 76}
 77
 78static inline void img_pwm_writel(struct img_pwm_chip *imgchip,
 79				  u32 reg, u32 val)
 80{
 81	writel(val, imgchip->base + reg);
 82}
 83
 84static inline u32 img_pwm_readl(struct img_pwm_chip *imgchip, u32 reg)
 
 85{
 86	return readl(imgchip->base + reg);
 87}
 88
 89static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 90			  int duty_ns, int period_ns)
 91{
 92	u32 val, div, duty, timebase;
 93	unsigned long mul, output_clk_hz, input_clk_hz;
 94	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
 95	unsigned int max_timebase = imgchip->data->max_timebase;
 96	int ret;
 97
 98	if (period_ns < imgchip->min_period_ns ||
 99	    period_ns > imgchip->max_period_ns) {
100		dev_err(pwmchip_parent(chip), "configured period not in range\n");
101		return -ERANGE;
102	}
103
104	input_clk_hz = clk_get_rate(imgchip->pwm_clk);
105	output_clk_hz = DIV_ROUND_UP(NSEC_PER_SEC, period_ns);
106
107	mul = DIV_ROUND_UP(input_clk_hz, output_clk_hz);
108	if (mul <= max_timebase) {
109		div = PWM_CTRL_CFG_NO_SUB_DIV;
110		timebase = DIV_ROUND_UP(mul, 1);
111	} else if (mul <= max_timebase * 8) {
112		div = PWM_CTRL_CFG_SUB_DIV0;
113		timebase = DIV_ROUND_UP(mul, 8);
114	} else if (mul <= max_timebase * 64) {
115		div = PWM_CTRL_CFG_SUB_DIV1;
116		timebase = DIV_ROUND_UP(mul, 64);
117	} else if (mul <= max_timebase * 512) {
118		div = PWM_CTRL_CFG_SUB_DIV0_DIV1;
119		timebase = DIV_ROUND_UP(mul, 512);
120	} else {
121		dev_err(pwmchip_parent(chip),
122			"failed to configure timebase steps/divider value\n");
123		return -EINVAL;
124	}
125
126	duty = DIV_ROUND_UP(timebase * duty_ns, period_ns);
127
128	ret = pm_runtime_resume_and_get(pwmchip_parent(chip));
129	if (ret < 0)
130		return ret;
131
132	val = img_pwm_readl(imgchip, PWM_CTRL_CFG);
133	val &= ~(PWM_CTRL_CFG_DIV_MASK << PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm));
134	val |= (div & PWM_CTRL_CFG_DIV_MASK) <<
135		PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm);
136	img_pwm_writel(imgchip, PWM_CTRL_CFG, val);
137
138	val = (duty << PWM_CH_CFG_DUTY_SHIFT) |
139	      (timebase << PWM_CH_CFG_TMBASE_SHIFT);
140	img_pwm_writel(imgchip, PWM_CH_CFG(pwm->hwpwm), val);
141
142	pm_runtime_mark_last_busy(pwmchip_parent(chip));
143	pm_runtime_put_autosuspend(pwmchip_parent(chip));
144
145	return 0;
146}
147
148static int img_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
149{
150	u32 val;
151	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
152	int ret;
153
154	ret = pm_runtime_resume_and_get(pwmchip_parent(chip));
155	if (ret < 0)
156		return ret;
157
158	val = img_pwm_readl(imgchip, PWM_CTRL_CFG);
159	val |= BIT(pwm->hwpwm);
160	img_pwm_writel(imgchip, PWM_CTRL_CFG, val);
161
162	regmap_clear_bits(imgchip->periph_regs, PERIP_PWM_PDM_CONTROL,
163			  PERIP_PWM_PDM_CONTROL_CH_MASK <<
164			  PERIP_PWM_PDM_CONTROL_CH_SHIFT(pwm->hwpwm));
165
166	return 0;
167}
168
169static void img_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
170{
171	u32 val;
172	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
173
174	val = img_pwm_readl(imgchip, PWM_CTRL_CFG);
175	val &= ~BIT(pwm->hwpwm);
176	img_pwm_writel(imgchip, PWM_CTRL_CFG, val);
177
178	pm_runtime_mark_last_busy(pwmchip_parent(chip));
179	pm_runtime_put_autosuspend(pwmchip_parent(chip));
180}
181
182static int img_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
183			 const struct pwm_state *state)
184{
185	int err;
186
187	if (state->polarity != PWM_POLARITY_NORMAL)
188		return -EINVAL;
189
190	if (!state->enabled) {
191		if (pwm->state.enabled)
192			img_pwm_disable(chip, pwm);
193
194		return 0;
195	}
196
197	err = img_pwm_config(chip, pwm, state->duty_cycle, state->period);
198	if (err)
199		return err;
200
201	if (!pwm->state.enabled)
202		err = img_pwm_enable(chip, pwm);
203
204	return err;
205}
206
207static const struct pwm_ops img_pwm_ops = {
208	.apply = img_pwm_apply,
 
 
 
209};
210
211static const struct img_pwm_soc_data pistachio_pwm = {
212	.max_timebase = 255,
213};
214
215static const struct of_device_id img_pwm_of_match[] = {
216	{
217		.compatible = "img,pistachio-pwm",
218		.data = &pistachio_pwm,
219	},
220	{ }
221};
222MODULE_DEVICE_TABLE(of, img_pwm_of_match);
223
224static int img_pwm_runtime_suspend(struct device *dev)
225{
226	struct pwm_chip *chip = dev_get_drvdata(dev);
227	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
228
229	clk_disable_unprepare(imgchip->pwm_clk);
230	clk_disable_unprepare(imgchip->sys_clk);
231
232	return 0;
233}
234
235static int img_pwm_runtime_resume(struct device *dev)
236{
237	struct pwm_chip *chip = dev_get_drvdata(dev);
238	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
239	int ret;
240
241	ret = clk_prepare_enable(imgchip->sys_clk);
242	if (ret < 0) {
243		dev_err(dev, "could not prepare or enable sys clock\n");
244		return ret;
245	}
246
247	ret = clk_prepare_enable(imgchip->pwm_clk);
248	if (ret < 0) {
249		dev_err(dev, "could not prepare or enable pwm clock\n");
250		clk_disable_unprepare(imgchip->sys_clk);
251		return ret;
252	}
253
254	return 0;
255}
256
257static int img_pwm_probe(struct platform_device *pdev)
258{
259	int ret;
260	u64 val;
261	unsigned long clk_rate;
262	struct pwm_chip *chip;
263	struct img_pwm_chip *imgchip;
264
265	chip = devm_pwmchip_alloc(&pdev->dev, IMG_PWM_NPWM, sizeof(*imgchip));
266	if (IS_ERR(chip))
267		return PTR_ERR(chip);
268	imgchip = to_img_pwm_chip(chip);
269
270	imgchip->base = devm_platform_ioremap_resource(pdev, 0);
271	if (IS_ERR(imgchip->base))
272		return PTR_ERR(imgchip->base);
273
274	imgchip->data = device_get_match_data(&pdev->dev);
275
276	imgchip->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
277							       "img,cr-periph");
278	if (IS_ERR(imgchip->periph_regs))
279		return PTR_ERR(imgchip->periph_regs);
 
 
 
 
 
 
280
281	imgchip->sys_clk = devm_clk_get(&pdev->dev, "sys");
282	if (IS_ERR(imgchip->sys_clk)) {
283		dev_err(&pdev->dev, "failed to get system clock\n");
284		return PTR_ERR(imgchip->sys_clk);
285	}
286
287	imgchip->pwm_clk = devm_clk_get(&pdev->dev, "pwm");
288	if (IS_ERR(imgchip->pwm_clk)) {
289		dev_err(&pdev->dev, "failed to get pwm clock\n");
290		return PTR_ERR(imgchip->pwm_clk);
291	}
292
293	platform_set_drvdata(pdev, chip);
 
 
 
 
294
295	pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_PWM_PM_TIMEOUT);
296	pm_runtime_use_autosuspend(&pdev->dev);
297	pm_runtime_enable(&pdev->dev);
298	if (!pm_runtime_enabled(&pdev->dev)) {
299		ret = img_pwm_runtime_resume(&pdev->dev);
300		if (ret)
301			goto err_pm_disable;
302	}
303
304	clk_rate = clk_get_rate(imgchip->pwm_clk);
305	if (!clk_rate) {
306		dev_err(&pdev->dev, "imgchip clock has no frequency\n");
307		ret = -EINVAL;
308		goto err_suspend;
309	}
310
311	/* The maximum input clock divider is 512 */
312	val = (u64)NSEC_PER_SEC * 512 * imgchip->data->max_timebase;
313	do_div(val, clk_rate);
314	imgchip->max_period_ns = val;
315
316	val = (u64)NSEC_PER_SEC * MIN_TMBASE_STEPS;
317	do_div(val, clk_rate);
318	imgchip->min_period_ns = val;
319
320	chip->ops = &img_pwm_ops;
 
 
 
321
322	ret = pwmchip_add(chip);
323	if (ret < 0) {
324		dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret);
325		goto err_suspend;
326	}
327
 
328	return 0;
329
330err_suspend:
331	if (!pm_runtime_enabled(&pdev->dev))
332		img_pwm_runtime_suspend(&pdev->dev);
333err_pm_disable:
334	pm_runtime_disable(&pdev->dev);
335	pm_runtime_dont_use_autosuspend(&pdev->dev);
336	return ret;
337}
338
339static void img_pwm_remove(struct platform_device *pdev)
340{
341	struct pwm_chip *chip = platform_get_drvdata(pdev);
342
343	pm_runtime_disable(&pdev->dev);
344	if (!pm_runtime_status_suspended(&pdev->dev))
345		img_pwm_runtime_suspend(&pdev->dev);
346
347	pwmchip_remove(chip);
348}
349
350#ifdef CONFIG_PM_SLEEP
351static int img_pwm_suspend(struct device *dev)
352{
353	struct pwm_chip *chip = dev_get_drvdata(dev);
354	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
355	int i, ret;
356
357	if (pm_runtime_status_suspended(dev)) {
358		ret = img_pwm_runtime_resume(dev);
359		if (ret)
360			return ret;
361	}
362
363	for (i = 0; i < chip->npwm; i++)
364		imgchip->suspend_ch_cfg[i] = img_pwm_readl(imgchip,
365							   PWM_CH_CFG(i));
366
367	imgchip->suspend_ctrl_cfg = img_pwm_readl(imgchip, PWM_CTRL_CFG);
368
369	img_pwm_runtime_suspend(dev);
370
371	return 0;
372}
373
374static int img_pwm_resume(struct device *dev)
375{
376	struct pwm_chip *chip = dev_get_drvdata(dev);
377	struct img_pwm_chip *imgchip = to_img_pwm_chip(chip);
378	int ret;
379	int i;
380
381	ret = img_pwm_runtime_resume(dev);
382	if (ret)
383		return ret;
384
385	for (i = 0; i < chip->npwm; i++)
386		img_pwm_writel(imgchip, PWM_CH_CFG(i),
387			       imgchip->suspend_ch_cfg[i]);
388
389	img_pwm_writel(imgchip, PWM_CTRL_CFG, imgchip->suspend_ctrl_cfg);
390
391	for (i = 0; i < chip->npwm; i++)
392		if (imgchip->suspend_ctrl_cfg & BIT(i))
393			regmap_clear_bits(imgchip->periph_regs,
394					  PERIP_PWM_PDM_CONTROL,
395					  PERIP_PWM_PDM_CONTROL_CH_MASK <<
396					  PERIP_PWM_PDM_CONTROL_CH_SHIFT(i));
397
398	if (pm_runtime_status_suspended(dev))
399		img_pwm_runtime_suspend(dev);
400
401	return 0;
402}
403#endif /* CONFIG_PM */
404
405static const struct dev_pm_ops img_pwm_pm_ops = {
406	SET_RUNTIME_PM_OPS(img_pwm_runtime_suspend,
407			   img_pwm_runtime_resume,
408			   NULL)
409	SET_SYSTEM_SLEEP_PM_OPS(img_pwm_suspend, img_pwm_resume)
410};
411
412static struct platform_driver img_pwm_driver = {
413	.driver = {
414		.name = "img-pwm",
415		.pm = &img_pwm_pm_ops,
416		.of_match_table = img_pwm_of_match,
417	},
418	.probe = img_pwm_probe,
419	.remove_new = img_pwm_remove,
420};
421module_platform_driver(img_pwm_driver);
422
423MODULE_AUTHOR("Sai Masarapu <Sai.Masarapu@imgtec.com>");
424MODULE_DESCRIPTION("Imagination Technologies PWM DAC driver");
425MODULE_LICENSE("GPL v2");